Schmoker J D, Zhuang J, Shackford S R, Pietropaoli J
Department of Surgery, University of Vermont College of Medicine, Burlington.
J Trauma. 1993 Oct;35(4):627-35; discussion 635-6. doi: 10.1097/00005373-199310000-00020.
Cerebral blood flow (CBF) varies unpredictably in patients after head injury and hemorrhagic shock. Proper treatment requires knowledge of ischemic versus hyperemic flow. The degree to which the size or severity of the injury may contribute to CBF abnormalities is unknown. We hypothesized that lesion size is a determinant of postinjury CBF. We measured cerebral and systemic variables in a porcine model of focal cryogenic brain injury and hemorrhagic shock over a 5-hour period. Swine were randomized to receive either a large or small lesion followed by hemorrhage. In the small lesion group traumatic brain injury, followed by shock and resuscitation, produced a significant and sustained elevation in bihemispheric regional CBF and cerebral oxygen delivery that was significantly greater than that observed in either the large lesion group or the controls (p < 0.05). There were no significant differences between the experimental groups in volume of hemorrhage, intracranial pressure, cerebral perfusion pressure, arterial oxygen content, or PaCO2. These data suggest that the volume of injured tissue may determine post-resuscitation CBF, and that interventions to reduce cerebral blood volume (i.e., hyperventilation) may not be universally applicable in all head injured patients.
颅脑损伤和失血性休克患者的脑血流量（CBF）变化不可预测。恰当的治疗需要了解缺血性血流与充血性血流情况。损伤的大小或严重程度在多大程度上会导致CBF异常尚不清楚。我们假设损伤大小是伤后脑血流量的一个决定因素。我们在一个猪的局灶性低温脑损伤和失血性休克模型中，在5小时内测量了脑和全身的变量。猪被随机分为接受大或小损伤然后出血的两组。在小损伤组中，创伤性脑损伤后再进行休克和复苏，导致双半球局部CBF和脑氧输送显著且持续升高，显著高于大损伤组或对照组（p < 0.05）。实验组之间在出血量、颅内压、脑灌注压、动脉血氧含量或动脉血二氧化碳分压方面没有显著差异。这些数据表明，受伤组织的体积可能决定复苏后脑血流量，并且减少脑血容量的干预措施（即过度通气）可能并非普遍适用于所有颅脑损伤患者。
